Tuesday, January 5, 2010

The Tupolev Tu-95 Bear: World’s Noisiest Aircraft Ever?

As Russia’s oldest serving strategic bomber that had been in service since 1955, does it really deserve as the world’s noisiest aircraft ever?

By: Ringo Bones

How does something qualify as extremely noisy? Well, if a certain airplane’s engine noise could create so much noise that SONAR arrays meant to track submarines can hear it, then yes. Believe it or not, the four counter-rotating propeller array driven by the Tu-95 Bear’s four powerful gas turbine engine produces so much noise. That the long-range bomber’s engines’ unique harmonics can be heard by the SONAR Surveillance System of the US Navy – i.e. SOSAS – meant to track Soviet era submarines during the height of the Cold War. Which kind of makes me think why former Alaskan governor Sarah Palin has never ever been temporarily deafened by a squadron of Tu-95 Bears when she claimed during the 2008 US Presidential Elections that she can see Russia from her front porch.

At present, fleets of Russia’s Tu-95 Bear is paradoxically adopted in its new mission to fire long-range cruise missiles at the US Navy’s Carrier Group. Given that a retinue of antisubmarine warfare ships and aircraft, not to mention escorted by an attack submarine is what constitutes a typical US Navy Carrier Group. The chances of the Tu-95 coming within a thousand miles of an American aircraft carrier without registering on the SONAR screens of the support craft is highly unlikely due to the aircraft’s very high noise level. With these inherent problems, why did the Soviet Union even allowed such a plane to be operational in the first place and most of all, what is the source of this aircraft’s “noise problem”?

Back when Josef Stalin was still running the Soviet Union and their top scientists just developed their very own A-bomb. Ballistic missiles that can reach the continental United States were yet to be invented. Due to the inherent fiscal austerity of a Marxist-Leninist socialist system, the Soviets can’t afford to build numerous pristine 10,000-foot runways like the United States has done since World War II. So during the design stage, Soviet aeronautical engineers chose to equip their premier strategic bomber with counter-rotating props attached to an extremely powerful gas turbine engine. Which was a very reasonable choice at the time if they want their premier strategic bomber to have the capability to nuke New York or Washington D.C. when operating from Soviet soil. Besides, fuel-efficient pure jet engines are yet to be invented that could enable the Tu-95 Bear to fulfill it’s designed mission.

Counter-rotating propellers made the Tu-95 Bear not so addicted to 10,000 feet long pristine concrete runways and the counter-rotating turboprop configuration allowed it to fly comfortably at a little over 500 mph for 10 hours or so. But it did create so much noise at levels that are probably hell for the ground crew when a squadron of these are lining up for take-off with the planes’ engines revving to full power. For such a plane to fly at 500 miles per hour, its propeller tip speed would be moving at supersonic speeds. At such speeds, not only is the “thrust efficiency” of the propeller is reduced, those very propellers would be producing a sonic boom every time it rotates. To the ground crew, a squadron of Tu-95 Bears lining up for take-off could sound like a large battalion of anti-aircraft gun batteries firing in unison. One can only imagine the noise levels experienced by a typical pilot, bombardier-navigator and tail gunner of a Tu-95 Bear on a 10-hour mission.

At about the same time, the US Navy was also flirting with a supersonic capable propeller driven fighter aircraft that can easily take off from and land on an aircraft carrier. At the time, steam catapult technology was still at its infancy so they tried to attach a jet turbine driven propeller to a modified F-100 Super Sabre jet to enable it to easily take-off from and land on the flight deck of an aircraft carrier. Unfortunately, the modified propeller-equipped Super Sabre jet produced so much noise that it had given flight deck crew malaise and nausea due to excessive noise exposure. And the propeller-equipped Super Sabre jet never managed to reach supersonic speeds despite of its improved carrier-based take-off and landing performance.

Airport Security: Air Travel Safety’s Weakest Link?

With the failed Christmas Day 2009 terror attack almost becoming as tragic as 9 / 11, is our overly intrusive – but woefully inadequate airport security – the weakest link in the air travel safety chain?

By: Ringo Bones

December 25, 2009 would have been a very tragic if a young radicalized Al-Qaeda recruit managed to replicate the Lockerbie terror attack. Fortunately, the improvised airport security evading explosive device carried by the would-be suicide bomber failed to explode. Making the 23 year old Nigerian named Omar Farouk Abdul Mutallab to top the notoriety list when 2009 draws to a close. But the averted tragedy does raise the question whether our overly intrusive from a Civil Liberties standpoint – but woefully inadequate – airport passenger screening and security procedures need to be upgraded?

Technological solutions only solve some of the aspects of the still evolving menace of global terrorism. Those newfangled X-Ray back-scatter based and millimeter wave technology explosive detection and scanners whose working prototypes became operational around 1999 to 2000 are still so controversial because they can outline with almost photographic fidelity the bodies of the subjects they are examining. By making their intimate details clearly visible on the display screen as if the scanned subjects were naked. The EU had been unanimous in deferring their use in major European airports even after the 9 / 11 terror attacks due to their overt intrusiveness. Major airports under the jurisdiction of Number 10 Downing Street have now resorted in using these overtly intrusive scanners in an effort to bolster airport security.

These newfangled devices’ ability to detect PETN-based explosive devices – like the one used in the failed Christmas Day attack - are just about within the limits of these security scanners operational effectiveness. So a terrorist using such bombs still has a possibility of slipping through such newfangled security scanners. Our design paradigm for weapons detection has always been aimed at detecting ferromagnetic material based weapons systems – not the ambient chemical residues of nitrate based explosives. Sadder still, bomb sniffing dogs can't verbally alert their handlers that they have a cold or coming down with something and full body pat downs are just too over-the-top intrusive to some people's sensibilities when it comes to Civil Liberty issues.

Sadly, most of us - including the powers that be - are just treating the symptoms, not the cause, of global terrorism. Even though the averted tragedy of the failed Christmas Day terror attack was eventually blamed – yet again – to the various intelligence agencies failure to coordinate and communicate in their operations, the incident will very likely won’t be the last. Other threats to the safely of air travel – like bird strikes and poor aircraft maintenance – will again be deprived of the much needed R & D funding. Overtly intrusive and Civil Liberties violating methods of scanning our own person and personal belongings in airports are now the lucrative draw of research and development money. Lets just hope that all of our airline pilots are as good as Captain Chesley Sullenberger in averting the worst effects of a bird strike incident.